OK, I think that I have to give up on looking for 2005 HAH with Navi since there are not that many to find and deal.

It is more likely to find the non-Navi 05 HAH.
Hopefully I can find an aftermarket Navi system to install into the HAH.

My concern is that some info shown on Honda navi screen is probably very helpful/cool to see and they may not be visible to any non-Honda navi system.

Is it a good idea to get a non-Navi first and then "upgrade" it later?